Frenchman Jonathan Verron, an alleged leader of a hacker group that stole data from a British financial institution and demanded a ransom to keep it secure, was arrested on Koh Samui on Friday.
Crime Suppression Division Fifth Command and Technology Crime Suppression Division police had French embassy staff on hand when they raided a house in Tambon Mae Nam at 5am.
They seized a quantity of marijuana and 20 pieces of evidence, including a computer, phone and bank passbooks.
Verron, initially charged with possession of marijuana, is expected to be quickly extradited to France.
He is alleged to have hacked into the computer system of a British financial institution, stole its customers’ personal information and demanded a ransom in exchange for not making the information public.
His two alleged accomplices are in custody in France.
French police learned that Verron, who is also accused of somehow involving in the "Dark Web" which is a platform where narcotics and war weapons were often traded, was in hiding in Thailand.
Courts in Surat Thani and Nakhon Ratchasima issued search warrants. The Samui raid was simultaneous with searches of two houses in Nakhon Ratchasima’s Pak Chong district.